The composition of the incipient melt of garnet peridotite at 7GPa and major element composition of the missing reservoir

Abstract

The difference in ¹⁴²Nd/¹⁴⁴Nd between present Bulk Silicate Earth and chondrites has been reported and this difference indicates a reservoir enriched in incompatible elements. Kondo & Kogiso (2014) discussed that the reservoir could be the solidus melt of peridotite at 7GPa. So in this study we determined the composition of the solidus melt from Modified Iterative Sandwich Experiment proposed by Hirschmann and Dasgupta (2007). Determined melt composition was komatiitic and conformable to the composition extrapolated from Walter (1998). The concentration of K and P in the solidus melt, however, was lower than in the expected melt and the reservoir would not have KREEPy composition.